Delivery of cardiac constraint jacket

ABSTRACT

A cardiac constraint jacket is formed of flexible material defining a volume between an open upper end and a lower end. The jacket is dimensioned for an apex of a patient&#39;s heart to be inserted into the volume through the open upper end and for the jacket to be slipped over the heart. A delivery device is used to place the jacket on the heart. The delivery device includes a plurality of attachment locations. Each of the attachment locations is releasably secured to separate positions surrounding a periphery of the open upper end of the jacket. The delivery device also includes a control arrangement which is selectively movable between an open position and a closed position. The control arrangement is connected to the attachment locations such that the attachment locations are in a compact array urging the open upper end of the jacket into a collapsed configuration when the control member is in the closed position. When the control arrangement is in the open position, the attachment locations are in an open array. The attachment locations urge the open upper end of the jacket into an open configuration sufficient for the heart to be inserted into the jacket volume through the open upper end and for the jacket to be slipped over said heart.

This application is a continuation of Ser. No. 10/766,987 filed Jan. 28,2004 (issuing Apr. 19, 2005 as U.S. Pat. No. 6,881,185) which is acontinuation of U.S. application Ser. No. 10/226,580, filed Aug. 23,2002, now U.S. Pat. No. 6,689,048 B2, which is a continuation of U.S.application Ser. No. 09/921,475, filed Aug. 3, 2001, now U.S. Pat. No.6,579,226 B2, which is a continuation of U.S. application Ser. No.09/483,567, filed Jan. 14, 2000, now U.S. Pat. No. 6,293,906 B1, whichapplications and patents are incorporated herein by reference and withclaim of priority being made to all such applications and theirrespective filing dates.

I. BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention pertains to a method and apparatus for treatingcongestive heart disease and related valvular dysfunction. Moreparticularly, the present invention is directed to an apparatus andmethod for delivery of a cardiac constraint jacket.

2. Description of the Prior Art

Congestive heart disease is a progressive and debilitating illness. Thedisease is characterized by a progressive enlargement of the heart.

As the heart enlarges, the heart is performing an increasing amount ofwork in order to pump blood each heart beat. In time, the heart becomesso enlarged the heart cannot adequately supply blood. An afflictedpatient is fatigued, unable to perform even simple exerting tasks andexperiences pain and discomfort. Further, as the heart enlarges, theinternal heart valves cannot adequately close. This impairs the functionof the valves and further reduces the heart's ability to supply blood.

Causes of congestive heart disease are not fully known. In certaininstances, congestive heart disease may result from viral infections. Insuch cases, the heart may enlarge to such an extent that the adverseconsequences of heart enlargement continue after the viral infection haspassed and the disease continues its progressively debilitating course.

Patients suffering from congestive heart disease are commonly groupedinto four classes (i.e., Classes I, II, III and IV). In the early stages(e.g., Classes I and II), drug therapy is the most commonly prescribedtreatment. Drug therapy treats the symptoms of the disease and may slowthe progression of the disease. Importantly, there is no cure forcongestive heart disease. Even with drug therapy, the disease willprogress. Further, the drugs may have adverse side effects.

Presently, the only permanent treatment for congestive heart disease isheart transplant. To qualify, a patient must be in the later stage ofthe disease (e.g., Classes III and IV with Class IV patients givenpriority for transplant). Such patients are extremely sick individuals.Class III patients have marked physical activity limitations and ClassIV patients are symptomatic even at rest.

Due to the absence of effective intermediate treatment between drugtherapy and heart transplant, Class III and IV patients will havesuffered terribly before qualifying for heart transplant. Further, aftersuch suffering, the available treatment is unsatisfactory. Hearttransplant procedures are very risky, extremely invasive and expensiveand only shortly extend a patient's life. For example, prior totransplant, a Class IV patient may have a life expectancy of 6 months toone-year. Heart transplant may improve the expectancy to about fiveyears.

Unfortunately, not enough hearts are available for transplant to meetthe needs of congestive heart disease patients. In the United States, inexcess of 35,000 transplant candidates compete for only about 2,000transplants per year. A transplant waiting list is about 8-12 monthslong on average and frequently a patient may have to wait about 1-2years for a donor heart. While the availability of donor hearts hashistorically increased, the rate of increase is slowing dramatically.Even if the risks and expense of heart transplant could be tolerated,this treatment option is becoming increasingly unavailable. Further,many patients do not qualify for heart transplant due to failure to meetany one of a number of qualifying criteria

Congestive heart failure has an enormous societal impact. In the UnitedStates alone, about five million people suffer from the disease (ClassesI through IV combined). Alarmingly, congestive heart failure is one ofthe most rapidly accelerating diseases (about 400,000 new patients inthe United States each year). Economic costs of the disease have beenestimated at $38 billion annually.

Not surprising, substantial effort has been made to find alternativetreatments for congestive heart disease. Recently, a new surgicalprocedure has been developed. Referred to as the Batista procedure, thesurgical technique includes dissecting and removing portions of theheart in order to reduce heart volume. This is a radical new andexperimental procedure subject to substantial controversy. Furthermore,the procedure is highly invasive, risky and expensive and commonlyincludes other expensive procedures (such as a concurrent heart valvereplacement). Also, the treatment is limited to Class IV patients and,accordingly, provides no hope to patients facing ineffective drugtreatment prior to Class IV. Finally, if the procedure fails, emergencyheart transplant is the only available option.

Clearly, there is a need for alternative treatments applicable to bothearly and later stages of the disease to either stop the progressivenature of the disease or more drastically slow the progressive nature ofcongestive heart disease. Unfortunately, currently developed options areexperimental, costly and problematic.

Cardiomyoplasty is a recently developed treatment for earlier stagecongestive heart disease (e.g., as early as Class III dilatedcardiomyopathy). In this procedure, the latissimus dorsi muscle (takenfrom the patient's shoulder) is wrapped around the heart and chronicallypaced synchronously with ventricular systole. Pacing of the muscleresults in muscle contraction to assist the contraction of the heartduring systole.

Even though cardiomyoplasty has demonstrated symptomatic improvement,studies suggest the procedure only minimally improves cardiacperformance. The procedure is highly invasive requiring harvesting apatient's muscle and an open chest approach (i.e., stemotomy) to accessthe heart. Furthermore, the procedure is expensive—especially thoseusing a paced muscle. Such procedures require costly pacemakers. Thecardiomyoplasty procedure is complicated. For example, it is difficultto adequately wrap the muscle around the heart with a satisfactory fit.Also, if adequate blood flow is not maintained to the wrapped muscle,the muscle may necrose. The muscle may stretch after wrapping reducingits constraining benefits and is generally not susceptible topostoperative adjustment. Finally, the muscle may fibrose and adhere tothe heart causing undesirable constraint on the contraction of the heartduring systole.

While cardiomyoplasty has resulted in symptomatic improvement, thenature of the improvement is not understood. For example, one study hassuggested the benefits of cardiomyoplasty are derived less from activesystolic assist than from remodeling, perhaps because of an externalelastic constraint. The study suggests an elastic constraint (i.e., anon-stimulated muscle wrap or an artificial elastic sock placed aroundthe heart) could provide similar benefits. Kass et al., ReverseRemodeling From Cardiomyoplasty In Human Heart Failure: ExternalConstraint Versus Active Assist, 91 Circulation 2314-2318 (1995).Similarly, cardiac binding is described in Oh et al., The Effects ofProsthetic Cardiac Binding and Adynamic Cardiomyoplasty in a Model ofDilated Cardiomyopathy, 116 J. Thorac. Cardiovasc. Surg. 148-153 (1998),Vaynblat et al., Cardiac Binding in Experimental Heart Failure, 64 Ann.Thorac. Surg. 81-85 (1997) and Capouya et al., Girdling Effect ofNonstimulated Cardiomyoplasty on Left Ventricular Function, 56 Ann.Thorac. Surg. 867-871 (1993).

In addition to cardiomyoplasty, mechanical assist devices have beendeveloped as intermediate procedures for treating congestive heartdisease. Such devices include left ventricular assist devices (“LVAD”)and total artificial hearts (“TAH”). An LVAD includes a mechanical pumpfor urging blood flow from the left ventricle into the aorta. Suchsurgeries are expensive. The devices are at risk of mechanical failureand frequently require external power supplies. TAH devices are used astemporary measures while a patient awaits a donor heart for transplant.

Commonly assigned U.S. Pat. No. 5,702,343 to Alferness dated Dec. 30,1997 teaches a jacket to constrain cardiac expansion during diastole.Also, PCT International Publication No. WO 98/29401 published Jul. 9,1998 teaches a cardiac constraint in the form of surfaces on oppositesides of the heart with the surfaces joined together by a cable throughthe heart or by an external constraint. U.S. Pat. No. 5,800,528 datedSep. 1, 1998 teaches a passive girdle to surround a heart. Germanutility model DE 295 17 393 describes a non-expansible heart pouch. PCTInternational Publication No. WO 98/58598 published Dec. 30, 1998describes a cardiac pouch with an elastic limit.

A cardiac constraint device can be placed on an enlarged heart andfitted snug during diastole. For example, a knit jacket device can beloosely slipped on the heart. After such placement, the material of thejacket can be gathered to adjust the device to a desired tension. Thegathered material can be sutured or otherwise fixed to maintain thetensioning. The heart may be pre-shrunk prior to placement of the deviceor the device may be fitted on the heart without pre-shrinking theheart. The device is adjusted to a snug fit on the heart duringdiastole.

When placing a cardiac constraint jacket around a heart, surgical accessis made to the heart. Such access may include a full sternotomy wherethe sternum is split lengthwise and separated to expose the heart.Recognizing such a procedure is highly traumatic, cardiac surgerycontinues to explore new surgical techniques ad tools to access theheart through less invasive procedures. Also, when placing the cardiacconstraint jacket on the heart, it may be necessary to manipulate theheart. Excessive manipulation is undesirable since the heart may respondby fibrillating requiring the surgeon to exercise defibrillatingprocedures or therapies.

The present invention is directed to improved methods and apparatus todeliver the cardiac constraint device.

II. SUMMARY OF THE INVENTION

According to a preferred embodiment of the present invention, a methodand apparatus are disclosed for treating congestive heart disease andrelated cardiac complications such as valvular disorders. A cardiacconstraint jacket is formed of flexible material defining a volumebetween an open upper end and a lower end. The jacket is dimensioned foran apex of a patient's heart to be inserted into the volume through theopen upper end and for the jacket to be slipped over the heart. Adelivery device is used in placing the jacket on the heart. In preferredembodiments, the delivery device includes a plurality of attachmentlocations. Each of the attachment locations is releasably secured atpositions surrounding a periphery of the open upper end of the jacket.The delivery device also includes a control arrangement selectivelymovable between an open position and a closed position. The controlarrangement is operatively connected to some or all of the attachmentlocations. The control arrangement can be selectively moved to a closedor open position. When in the closed position, the attachment locationsare in a compact array position, which urges the open upper end of thejacket into a collapsed configuration. When the control arrangement isin an open position, the attachment locations are in an open array whichurges the open upper end of the jacket into an open configurationsufficient for the heart to be inserted into the jacket volume throughthe open upper end for the jacket to be slipped over the heart.

According to the invention, the open end of the jacket may be releasablysecured to the attachment locations with the control arrangement movedto the closed position. In the closed position, the delivery device andjacket can be advanced toward the apex of the heart through a restrictedspace. The control arrangement can then be moved to an open positionwhen the open end of the jacket has passed through the restricted spaceand is in proximity to the apex for placement of the jacket on theheart.

III. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic cross-sectional view of a normal, healthy humanheart shown during systole;

FIG. 1A is the view of FIG. 1 showing the heart during diastole;

FIG. 2 is a schematic cross-sectional view of a diseased human heartshown during systole;

FIG. 2A is the view of FIG. 2 showing the heart during diastole;

FIG. 3 is a perspective view of a cardiac constraint device;

FIG. 3A is a side elevation view of a diseased heart in diastole withthe device of FIG. 3 in place;

FIG. 4 is a perspective view of an alternative cardiac constraintdevice;

FIG. 4A is a side elevation view of a diseased heart in diastole withthe device of FIG. 4 in place;

FIG. 5 is a cross-sectional view of the device of FIG. 3 overlying amyocardium and with the material of the device gathered for a snug fit;

FIG. 6 is a longitudinal cross-sectional view of one embodiment of adelivery tool of the invention shown in an open position;

FIG. 7 is the delivery tool of FIG. 6 in a closed position;

FIG. 8 is a perspective view showing a distal end of the tool of FIGS. 6and 7 with attached jacket of FIG. 3 in use placing the jacket on aheart;

FIG. 9 is a side view of an alternative embodiment of a delivery tool ofthe invention shown in an open position;

FIG. 10 is a side view of the delivery tool of FIG. 9 in a closedposition;

FIG. 11 is a side view of a patient showing relative placement ofinternal organs to illustrate a method according to the presentinvention;

FIG. 12 is a side view of an alternative embodiment of attachmentlocations of a spacing arm for a delivery tool of the invention;

FIG. 13 is a side sectional view of an alternative embodiment of aspacing arm for the present invention for delivery of a bio-adhesive;

FIG. 14 is a side sectional view of a further alternative embodiment ofa spacing arm for the present invention for delivery of a fasteningmember shown prior to delivery of the fastening member;

FIG. 15 is the view of FIG. 14 shown following delivery of the fasteningmember; and

FIG. 16 is a side sectional view of a still further alternativeembodiment of a spacing arm for the present invention for releasableattachment to a cardiac constraint jacket.

IV. DESCRIPTION OF THE PREFERRED EMBODIMENT

A. Congestive Heart Disease

To facilitate a better understanding of the present invention,description will first be made of a cardiac constraint device such as ismore fully described in commonly assigned and copending U.S. patentapplication Ser. No. 09/114,757 filed Jul. 13, 1998. In the drawings,similar elements are labeled similarly throughout.

With initial reference to FIGS. 1 and 1A, a normal, healthy human heartH′ is schematically shown in cross-section and will now be described inorder to facilitate an understanding of the present invention. In FIG.1, the heart H′ is shown during systole (i.e., high left ventricularpressure). In FIG. 1A, the heart H′ is shown during diastole (i.e., lowleft ventricular pressure).

The heart H′ is a muscle having an outer wall or myocardium MYO′ and aninternal wall or septum S′. The myocardium MYO′ and septum S′ definefour internal heart chambers including a right atrium RA′, a left atriumLA′, a right ventricle RV′ and a left ventricle LV′. The heart H′ has alength measured along a longitudinal axis BB′-AA′ from an tipper end orbase B′ to a lower end or apex A′.

The right and left atria RA′, LA′ reside in an upper portion UP′ of theheart H′ adjacent the base B′. The right and left ventricles RV′, LV′reside in a lower portion LP′ of the heart H′ adjacent the apex A′. Theventricles RV′, LV′ terminate at ventricular lower extremities LEadjacent the apex A′ and spaced therefrom by the thickness of themyocardium MYO′.

Due to the compound curves of the upper and lower portions UP′, LP′, theupper and lower portions UP′, LP′ meet at a circumferential groovecommonly referred to as the A-V (atrio-ventricular) groove AVG′.Extending away from the upper portion UP′ are a plurality of major bloodvessels communicating with the chambers RA′, RV′, LA′, LV′. For ease ofillustration, only the superior vena cava SVC′, inferior vena cava IVC′and a left pulmonary vein LPV′ are shown as being representative.

The heart H′ contains valves to regulate blood flow between the chambersRA′, RV′, LA′, LV′ and between the chambers and the major vessels (e.g.,the superior vena cava SVC′, inferior vena cava IVC′ and a leftpulmonary vein LPV′). For ease of illustration, not all of such valvesare shown. Instead, only the tricuspid valve TV′ between the rightatrium RA′ and right ventricle RV′ and the mitral valve MV′ between theleft atrium LA′ and left ventricle LV′ are shown as beingrepresentative.

The valves are secured, in part, to the myocardium MYO′ in a region ofthe lower portion LP′ adjacent the A-V groove AVG′ and referred to asthe valvular annulus VA′. The valves TV′ and MV′ open and close throughthe beating cycle of the heart H.

FIGS. 1 and 1A show a normal, healthy heart H′ during systole anddiastole, respectively. During systole (FIG. 1), the myocardium MYO′ iscontracting and the heart assumes a shape including a generally conicallower portion LP′. During diastole (FIG. 1A), the heart H′ is expandingand the conical shape of the lower portion LP′ bulges radially outwardly(relative to axis AA′-BB′).

The motion of the heart H′ and the variation in the shape of the heartH′ during contraction and expansion is complex. The amount of motionvaries considerably throughout the heart H′. The motion includes acomponent which is parallel to the axis AA′-BB′ (conveniently referredto as longitudinal expansion or contraction). The motion also includes acomponent perpendicular to the axis AA′-BB′ (conveniently referred to ascircumferential expansion or contraction).

Having described a healthy heart H′ during systole (FIG. 1) and diastole(FIG. 1A), comparison can now be made with a heart deformed bycongestive heart disease. Such a heart H is shown in systole in FIG. 2and in diastole in FIG. 2A. All elements of diseased heart H are labeledidentically with similar elements of healthy heart H′ except only forthe omission of the apostrophe in order to distinguish diseased heart Hfrom healthy heart H′.

Comparing FIGS. 1 and 2 (showing hearts H′ and H during systole), thelower portion LP of the diseased heart H has lost the tapered conicalshape of the lower portion LP′ of the healthy heart H′. Instead, thelower portion LP of the diseased heart H dilates outwardly between theapex A and the A-V groove AVG. So deformed, the diseased heart H duringsystole (FIG. 2) resembles the healthy heart H′ during diastole (FIG.1A). During diastole (FIG. 2A), the deformation is even more extreme.

As a diseased heart H enlarges from the representation of FIGS. 1 and 1Ato that of FIGS. 2 and 2A, the heart H becomes a progressivelyinefficient pump. Therefore, the heart H requires more energy to pumpthe same amount of blood. Continued progression of the disease resultsin the heart H being unable to supply adequate blood to the patient'sbody and the patient becomes symptomatic of cardiac insufficiency.

For ease of illustration, the progression of congestive heart diseasehas been illustrated and described with reference to a progressivedilation of the lower portion LP of the heart H. While such enlargementof the lower portion LP is most common and troublesome, enlargement ofthe upper portion UP may also occur.

In addition to cardiac insufficiency, the enlargement of the heart H canlead to valvular disorders. As the circumference of the valvular annulusVA increases, the leaflets of the valves TV and MV may spread apart.After a certain amount of enlargement, the spreading may be so severethe leaflets cannot completely close. Incomplete closure results invalvular regurgitation contributing to an additional degradation incardiac performance. While circumferential enlargement of the valvularannulus VA may contribute to valvular dysfunction as described, theseparation of the valve leaflets is most commonly attributed todeformation of the geometry of the heart H.

B. Cardiac Constraint Therapy

Having described the characteristics and problems of congestive heartdisease, a treatment method and apparatus are described in commonlyassigned and copending U.S. patent application Ser. No. 09/114,757 filedJul. 13, 1998. In general, a jacket is configured to surround themyocardium MYO. While the method of the present invention will bedescribed with reference to a jacket as described in commonly assignedand copending U.S. patent application Ser. No. 09/114,757 filed Jul. 13,1998, it will be appreciated the present invention is applicable to anycardiac constraint device including those shown in U.S. Pat. No.5,800,528 and PCT International Publication No. WO 98/29401. The entiredisclosure of each of these documents is incorporated herein byreference.

With reference now to FIGS. 3, 3A, 4 and 4A, the cardiac constraintdevice is shown as a jacket 10, 10′ of flexible, biologically compatiblematerial. The jacket 10, 10′ is an enclosed knit material having upperand lower ends 12, 12′, 14, 14′. The jacket 10, 10′ defines an internalvolume -16, 16′ which is completely enclosed but for the open ends 12,12′ and 14′. In the embodiment of FIG. 3, lower end 14 is closed. In theembodiment of FIG. 4, lower end 14′ is open. In both embodiments, upperends 12, 12′ are open. Throughout this description, the embodiment ofFIG. 3 will be discussed. Elements in common between the embodiments ofFIGS. 3 and 4 are numbered identically with the addition of anapostrophe to distinguish the second embodiment and such elements neednot be separately discussed.

The jacket 10 is dimensioned with respect to a heart H to be treated.Specifically, the jacket 10 is sized for the heart H to be constrainedwithin the volume 16. The jacket 10 can be slipped around the heart H.The jacket 10 has a length L between the upper and lower ends 12, 14sufficient for the jacket 10 to constrain the lower portion LP. Theupper end 12 of the jacket 10 preferably extends at least to A-V grooveAVG and further extends to the lower portion LP to constrain at leastthe lower ventricular extremities LE.

When the parietal pericardium is opened, the lower portion LP is free ofobstructions for applying the jacket 10 over the apex A. If, however,the parietal pericardium is intact, the diaphragmatic attachment to theparietal pericardium inhibits application of the jacket over the apex Aof the heart. In this situation, the jacket can be opened along a lineextending from the upper end 12′ to the lower end 14′ of jacket 10′. Thejacket can then be applied around the pericardial surface of the heartand the opposing edges of the opened line secured together after placedon the heart. Systems for securing the opposing edges are disclosed in,for example, U.S. Pat. No. 5,702,343, the entire disclosure of which isincorporated herein by reference. The lower end 14′ can then be securedto the diaphragm or associated tissues using, for example, sutures,staples, etc.

In the embodiment of FIGS. 3 and 3A, the lower end 14 is closed and thelength L is sized for the apex A of the heart H to be received withinthe lower end 14 when the upper end 12 is placed at the A-V groove AVG.In the embodiment of FIGS. 4 and 4A, the lower end 14′ is open and thelength L′ is sized for the apex A of the heart H to protrude beyond thelower end 14′ when the upper end 12′ is placed at the A-V groove AVG.The length L′ is sized so that the lower end 14′ extends beyond thelower ventricular extremities LE such that in both of jackets 10, 10′,the myocardium MYO surrounding the ventricles RV, LV is in directopposition to material of the jacket 10, 10′ during diastole. Suchplacement is desirable for the jacket 10, 10′ to present a constraintagainst dilation of the ventricular portions of the heart H.

After the jacket 10 is positioned on the heart H as described above, thejacket 10 is secured to the heart. Preferably, the jacket 10 is securedto the heart H using sutures (or other fastening means such as staples).The jacket 10 is sutured to the heart H at suture locations Scircumferentially spaced along the upper end 12. While a surgeon mayelect to add additional suture locations to prevent shifting of thejacket 10 after placement, the number of such locations S is preferablylimited so that the jacket 10 does not restrict contraction of the heartH during systole.

The jacket 10 constrains further undesirable circumferential enlargementof the heart while not impeding other motion of the heart H. With thebenefits of the present teachings, numerous modifications are possible.For example, the jacket 10 need not be directly applied to theepicardium (i.e., outer surface of the myocardium) but could be placedover the parietal pericardium. Further, an anti-fibrosis lining (such asa PTFE coating on the fibers of the knit) could be placed between theheart H and the jacket 10. Alternatively, the fibers 20 can be coatedwith PTFE.

The jacket 10 can be used in early stages of congestive heart disease.For patients facing heart enlargement due to viral infection, the jacket10 permits constraint of the heart H for a sufficient time to permit theviral infection to pass. In addition to preventing further heartenlargement, the jacket 10 treats valvular disorders by constrainingcircumferential enlargement of the valvular annulus and deformation ofthe ventricular walls.

C. Tensioning of the Jacket

To permit the jacket 10 to be easily placed on the heart H, the volumeand shape of the jacket 10 are larger than the lower portion LP duringdiastole. So sized, the jacket 10 may be easily slipped around the heartH. Once placed, the jacket's volume and shape are adjusted for thejacket 10 to snugly conform to the external geometry of the heart Hduring diastole. Such sizing is easily accomplished due to the knitconstruction of the jacket 10. For example, excess material of thejacket 10 can be gathered and sutured S″ (FIG. 5) to reduce the volume16 of the jacket 10 and conform the jacket 10 to the shape of the heartH during diastole. Such shape represents a maximum adjusted volume. Thejacket 10 constrains enlargement of the heart H beyond the maximumadjusted volume while preventing restricted contraction of the heart Hduring systole. As an alternative to gathering of FIG. 5, the jacket 10can be provided with other arrangements for adjusting and determiningthe volume of the jacket. For example, as disclosed in U.S. Pat. No.5,702,343, the jacket can be provided with a slot The jacket canalternatively include, for example, tension indicators as disclosed inco-pending U.S. Ser. No. 09/400,018 or tensioning arrangements asdisclosed in co-pending U.S. Ser. No. 09/400,019. The entire disclosureof each of these applications is hereby incorporated herein byreference.

The jacket 10 is adjusted to a snug fit on the heart H during diastole.Care is taken to avoid tightening the jacket 10 too much such thatcardiac function is impaired. During diastole, the left ventricle LVfills with blood. If the jacket 10 is too tight, the left ventricle LVcannot adequately expand and left ventricular pressure will rise. Duringthe fitting of the jacket 10, the surgeon can monitor left ventricularpressure. For example, a well-known technique for monitoring so-calledpulmonary wedge pressure uses a catheter placed in the pulmonary artery.The wedge pressure provides an indication of filling pressure in theleft atrium LA and left ventricle LV. While minor increases in pressure(e.g., 2-3 mm Hg) can be tolerated, the jacket 10 is snugly fit on theheart H but not so tight as to cause a significant increase in leftventricular pressure during diastole.

D. Delivery of the Jacket

The present invention is directed to methods and apparatuses forfacilitating delivery or application of a jacket through procedureswhich are less invasive and less traumatic as compared to fullsternotomy approaches. In general, an apparatus of the inventionprovides for compacting and passing a jacket through a minimallyinvasive opening into a patient's thorax and subsequently opening theupper end 12 of the jacket for passing over the heart. In someembodiments, the apparatus includes arrangements to facilitate securingthe jacket to the heart prior to removal of the apparatus from thethorax. The apparatuses of the invention can include a biasing memberwhich provides for collapsing and opening the upper end of the jacketthrough the use of components which permit selective alteration ofconfigurational states such as hinges, shape memory materials, elasticmaterials, springsteel, etc.

One embodiment of a delivery tool 30 is shown in FIGS. 6-8. FIGS. 6 and7 are schematic representations of the tool 30 in longitudinalcross-section and showing only two diametrically opposed spacing arms(as will be described) and showing the tool 30 in open (FIG. 6) andclosed (FIG. 7) positions (also, as will be described). FIG. 8 shows adistal end of the tool 30 with attached jacket 10 placed on a heart H.

The tool 30 includes a proximal handle 32 for hand-held manipulation bya surgeon. A plurality of attachment locations 34 are secured to thehandle 32 at a distal end of the tool 30. The attachment locations 34are preferably blunt, non-piercing and smooth, such as smooth plasticknobs, to avoid trauma to the patient as the attachment locations 34 areadvanced toward the heart H as will be described.

Each of the attachment locations 34 can be individually attached to thehandle 32 by a plurality of spacing arms 36. The spacing arms 36 can bestrips of flexible, elongated shape memory materials having straightportions 36 a and outwardly curved portions 36 b. In this embodiment,the spacing arms 36 are flat, narrow sheets of spring metal havingcurved portions 36 b configured for selective flexing toward and awayfrom axis X-X. The proximal ends of the straight portions 36 a can besecured to the handle 32. The attachment locations 34 are secured todistal ends of the curved portions 36 b.

The spacing arms 36 are secured to the handle 32 for the straightportions 36 a to be arranged in a closely compact cylindrical arrayaround the longitudinal axis X-X of the tool 30. In the open position,the curved portions 36 b curve outwardly from the axis X-X. Thus, theattachment locations 34 are disposed in a circular array around the axisX-X. In the embodiment of FIGS. 6-8, all spacing arms 36 are of equallength. As a result the circular array of the attachment locations 34 isin a plane perpendicular to the axis X-X. In an alternative embodiment,the lengths of the spacing arms 36 could vary. The curved portions 36 bprovide for attachment locations 34 to expand into an open configurationfor attachment locations 34 to be spaced from axis X-X by a distancesubstantially greater than the spacing of the straight portions 36 afrom the axis X-X.

FIGS. 6 and 7 show one embodiment of a control arrangement 38 forcontrolling the position of the attachment locations 34. The controlarrangement 38 shown here is a tube 39 which surrounds the straightportions 36 a of spacing arms 36. The control arrangement 38 is axiallyslidable along spacing arms 36 toward and away from the distal end ofthe tool 30. As the tube 39 is moved distally, the tube 39 slides overthe curved portions 36 b urging the curved portions 36 b and theconnected attachment locations 34 toward axis X-X. When the tube 39 ismoved proximally (i.e., the “open position”), the tube 39 is notcovering the curved portions 36 b. With the tube 39 in the openposition, the shape memory biases the spacing arms 36 to urge theattachment locations 34 to the spaced-apart open array. When the tube 39is moved distally to cover and compress the curved portions 36 b (i.e.,the “closed position”), the attachment locations 34 are urged to acompact array.

FIGS. 9 and 10 illustrate an alternative embodiment of a delivery tool40. In this embodiment, control arrangement 39 comprises a plurality ofdrawstrings 50 which connect to attachment locations 51 with the freeends 52 of drawstrings 50 passing through the handle 53. The surgeon canoperate the drawstrings 50 by pulling free ends 52. In the illustratedembodiment, pulling the drawstrings 50 urges the curved portions 54 b ofspacing arms 54 to the compact array position. Upon release of thedrawstrings 50, the spacing arms 54 return to a rest position therebymoving the attachment locations 51 to the open array position. It willbe appreciated that in the illustrated embodiment, the length of curvedportions 54 b of spacing arms 54 are not the same. The “posterior”spacing arms 54 c are longer than the “anterior” spacing arms 54 d.Thus, unlike delivery tool 30 of FIGS. 6 and 7, the circular array ofattachment locations 51 are not in a plane perpendicular to axis X-X.

Multiple drawstrings connected to separate sets of the attachmentlocations 51 could be employed. For example, the attachment locations 51could be divided into anterior and posterior sets representing anteriorand posterior placement of the attachment locations around the heart.Controlled by separate drawstrings 50, the anterior 54 d and posterior54 c sets could be separately manipulated by a surgeon.

The operation of a tool of the invention will now be described withreference to the tool 30 of FIGS. 6-8 and FIG. 10. However, it will beappreciated that the following discussion is applicable to all tools ofthe invention. Referring to FIGS. 6-8, a cardiac constraint device (suchas jacket 10 in FIG. 3) can be placed within the open array of theattachment locations. In FIG. 8, the open upper end 12 of the jacket 10is secured to the attachment locations by an attachment suture 42 passedthrough the material of the upper end 12 and further passed throughholes 40 formed in attachment locations 34. The lower end 14 of thejacket 10 faces the handle 32. The jacket 10 is surrounded by the curvedportions 36 b such that the jacket open end 12 is held open sufficientto receive an apex A of the heart H when the attachment locations 34 arein the open array.

Having described the mounting of the jacket to delivery tool 30, asurgical approach using tool 30 will now be described. With reference toFIG. 11, the heart H is positioned behind the sternum ST and behind thelungs LU. The heart H rests on the diaphragm DI. Not separately shown,the heart H is surrounded by the pericardium which forms a sack aroundthe heart H. The pericardium is attached to the diaphragm DI.

The present procedure will be described using a sub-xyphoid approach.However, it will be appreciated that the present invention is applicableto any procedure were a compact configuration of the jacket 10 isdesired to advance the jacket 10 toward the heart H.

The lower extremity of the sternum ST is called the xyphoid XI. Belowthe xyphoid, surgical access can be made to the chest cavity withoutneed for a sternotomy. After making a sub-xyphoid incision (and afterany desired pre-retraction of the lower end of the lung LU), a surgeoncan use the tool 30 to pass the jacket through the incision and placethe jacket 10 on the heart H. The placement of the jacket can bevisualized using known throscopic instrumentation and visualizationprocedures.

By moving the control arrangement 38 to the closed position, the distalend of the tool 30 (with attached jacket 10) can be inserted into thechest cavity through the incision and between the diaphragm DI and thelung LU. The jacket 10, curved portions 36 b of spacer arms 36 andattachment locations 34 are all constrained within the compact array.The distal end of the tool 30 can now be advanced toward the apex A ofthe heart H through the restricted space of the chest cavity. Duringsuch advancement, the blunt attachment locations 34 avoid trauma tothoracic structures.

The pericardium may be incised to permit access of the distal end to theapex A beneath the pericardium. When the distal end of tool 30 is at theapex A, the control arrangement 38 is moved to the open position. Thespacing arms 36 now urge the attachment locations 34 to the open arrayto open the upper end 12 of the jacket 10 sufficient to receive the apexA. With the control arrangement 38 in the open position, the distal endis passed around the apex A toward the base B of the heart H such thatthe jacket 10 is passed onto the heart. During such movement, the bluntattachment locations 34 can urge the pericardium away from the heart Hto create a space to receive the jacket 10.

After the jacket 10 is fully placed on the heart H, sutures S are placedbetween the open end 12 and the heart H securing the jacket 10 in placeon the heart. The attachment suture 42 is severed releasing the jacket10 from the attachment locations 34. The tool 30 can then be withdrawn.After the attachment locations 34 have passed the apex A, the controlarrangement 38 can be moved to the closed position and the tool 30 canbe withdrawn from the chest cavity.

With the present invention, access to the heart is made through arestricted space requiring a less traumatic surgical approach. Further,lifting and other substantial movement of the heart H can also bereduced or avoided.

Referring now to FIG. 12, in an alternative embodiment, an attachmentsuture 42 as described above may not be used to attach jacket 10 to thespacing arms of the tool. According to this embodiment, jacket 10includes a hem 60 having openings 61 into which can be inserted theattachment locations 62 of spacing arms 63. The previously describedcontrol arrangements and handles can be used according to thisembodiment of the invention.

Alternative embodiments of the distal end of spacing arms suitable forthe invention are shown in FIGS. 13-16. Each of the embodiments can beused with the tools described herein. For purposes here, elements incommon with each embodiment are similarly numbered (with the addition ofsingle, double and triple apostrophes to distinguish the embodiments).

In FIG. 13, the spacing arm 36′ terminates at the distal attachmentlocation 34′ having a hole 40′ to receive an attachment suture such assuture 42 in FIG. 8. The spacing arm 36′ is hollow to define an internalbore 70′ having a radial outlet 72′ facing the axis of the deliverytool. Therefore, in use, outlet 72′ faces both the upper end 12 of thejacket 10 and the heart H. A bio- or tissue-adhesive (e.g., fibrin glue)can be pumped through the bore 70′ and through outlet 72′ to adhere theopen end 12 of jacket 10 to the heart H. Such glue can be used inconjunction with or in lieu of the sutures S of FIG. 8.

In FIGS. 14 and 15, the spacing arm 36″ terminates at the distalattachment location 34″ having a hole 40″ to receive an attachmentsuture such as suture 42 in FIG. 8. The spacing arm 36″ is hollow todefine an internal bore 70″ having a radial outlet 72″ facing the axisof the delivery tool. In use, outlet 72″ faces both the upper end 12 ofthe jacket 10 and the heart H. A coil 76″ of metal or other suitablematerial is held in a straight configuration in the bore 70″ against thenatural coiling bias of the coil 76″. A push rod 74″ is slidablypositioned in the bore 70″ to push the coil 76″ out of outlet 72″ (asshown in FIG. 15). When pushed out of outlet 72″, the coil 76″penetrates through both the open end 12 of the jacket 10 and the heart Hand assumes its coiled shape thereby attaching the open end 12 of jacket10 to the heart H. Such a coil 76″ can be used in conjunction with or inlieu of the sutures S of FIG. 8.

In FIG. 16, the spacing arm 36′″ terminates at the distal attachmentlocation 34′″. The spacing arm 36′″ is hollow to define an internal bore70′″ having a radial outlet 72′″ facing the axis of the delivery tool.In use, outlet 72′″ faces both the open end 12 of the jacket 10 and theheart H. A rod 80′″ is disposed in bore 70′″ with a hooked end 82′″ atthe outlet 72′″. Pulling on rod 80′″ causes the hooked end 82′″ to bepulled into the bore 70′″. The open end 12 of the jacket 10 can beplaced near the outlet 72′″. The rod 80′″ can then be moved back to theposition of FIG. 16 with the hooked end 82′″ capturing the base 12 ofthe jacket. Like the embodiments of FIGS. 13-15, with the embodiment ofFIG. 16, the attachment suture 42 of FIG. 8 can be eliminated. Theembodiment of FIG. 16 can also be used in conjunction with theembodiments of FIGS. 13-15.

From the foregoing detailed description, the invention has beendescribed in a preferred embodiment. Modifications and equivalents ofthe disclosed concepts are intended to be included within the scope ofthe appended claims.

1. A cardiac jacket releasably mounted to a device for delivery of thecardiac jacket, comprising: a cardiac jacket for constraining expansionof a heart, the jacket having an open upper end portion, an open lowerend portion, a length and an internal volume sized to fit around a lowerportion of a heart; a tubular member having an open distal end exposinga tube interior sized to at least partially contain the cardiac jacket;and a plurality of rods releasably connected to the open upper endportion of the cardiac jacket and movable longitudinally relative tosaid tubular member between a retracted position with at least portionsof the cardiac jacket collapsed and contained within the tubular memberand an open position out of said distal end supporting the upper endportion of the cardiac jacket in a circular array, wherein the rods havelengths and shapes in the open position defining a volume at least asgreat as the internal volume of the cardiac jacket to enable the jacketto be slipped, upper end portion first, around the lower portion of theheart.
 2. A method for delivery of a cardiac jacket, said methodcomprising: selecting a delivery assembly including a cardiac jacket anda delivery device, said delivery device having: a tubular member havingan open distal end exposing a tube interior sized to at least partiallycontain said cardiac jacket; and a plurality of rods movablelongitudinally relative to said tubular member for urging said cardiacjacket out of said distal end and expanding said jacket to a placementshape selected to be placed on said heart; forming a minimally invasiveincision into a thoracic cavity of a patient; advancing said assemblythrough said incision toward said heart with said jacket within saidtubular member; moving said rods relative to said tubular member toexpand said jacket to said placement shape; and placing said jacket onsaid heart.
 3. A method according to claim 2 comprising releasing saidjacket from said rod.
 4. A cardiac jacket releasably mounted to a devicefor delivery of the cardiac jacket, comprising: an elastic cardiacjacket having an open upper end portion, a length and an internal volumesized to fit around a lower portion of a heart, wherein when in aneutral state the cardiac jacket has an internal volume that is smallerthan a volume of a heart onto which the cardiac jacket is to be fit; atubular member having an open distal end exposing a tube interior sizedto at least partially contain a the cardiac jacket; and a plurality ofrods releasably connected to the open upper end portion of the cardiacjacket and movable longitudinally relative to said tubular memberbetween a retracted position with at least portions of the cardiacjacket collapsed and contained within the tubular member and an openposition out of said distal end supporting the upper end portion of thecardiac jacket in a circular array, wherein the rods have lengths andshapes in the open position defining a volume at least as great as theinternal volume of the cardiac jacket to enable the jacket toelastically expand to an internal volume that is greater than theneutral state internal volume and be slipped, upper end portion first,around the lower portion of the heart.